X-Git-Url: https://git.openstreetmap.org./rails.git/blobdiff_plain/233a97bfcbee9c82027c049bb8bafac2693ec359..ebbead9701d91ba5499b816aab2614bdf53fa8e3:/app/models/changeset.rb diff --git a/app/models/changeset.rb b/app/models/changeset.rb index caa167c9e..4efd4f9e7 100644 --- a/app/models/changeset.rb +++ b/app/models/changeset.rb @@ -12,27 +12,60 @@ class Changeset < ActiveRecord::Base has_many :old_ways has_many :old_relations - validates_presence_of :user_id, :created_at, :open - validates_inclusion_of :open, :in => [ true, false ] - + validates_presence_of :id, :on => :update + validates_presence_of :user_id, :created_at, :closed_at, :num_changes + validates_uniqueness_of :id + validates_numericality_of :id, :on => :update, :integer_only => true + validates_numericality_of :min_lat, :max_lat, :min_lon, :max_lat, :allow_nil => true, :integer_only => true + validates_numericality_of :user_id, :integer_only => true + validates_numericality_of :num_changes, :integer_only => true, :greater_than_or_equal_to => 0 + validates_associated :user + + # over-expansion factor to use when updating the bounding box + EXPAND = 0.1 + + # maximum number of elements allowed in a changeset + MAX_ELEMENTS = 50000 + + # maximum time a changeset is allowed to be open for. + MAX_TIME_OPEN = 1.day + + # idle timeout increment, one hour seems reasonable. + IDLE_TIMEOUT = 1.hour + # Use a method like this, so that we can easily change how we # determine whether a changeset is open, without breaking code in at # least 6 controllers def is_open? - return open + # a changeset is open (that is, it will accept further changes) when + # it has not yet run out of time and its capacity is small enough. + # note that this may not be a hard limit - due to timing changes and + # concurrency it is possible that some changesets may be slightly + # longer than strictly allowed or have slightly more changes in them. + return ((closed_at > Time.now.getutc) and (num_changes <= MAX_ELEMENTS)) end + def set_closed_time_now + if is_open? + self.closed_at = Time.now.getutc + end + end + def self.from_xml(xml, create=false) begin - p = XML::Parser.new - p.string = xml + p = XML::Parser.string(xml) doc = p.parse cs = Changeset.new doc.find('//osm/changeset').each do |pt| if create - cs.created_at = Time.now + cs.created_at = Time.now.getutc + # initial close time is 1h ahead, but will be increased on each + # modification. + cs.closed_at = cs.created_at + IDLE_TIMEOUT + # initially we have no changes in a changeset + cs.num_changes = 0 end pt.find('tag').each do |tag| @@ -40,13 +73,67 @@ class Changeset < ActiveRecord::Base end end rescue Exception => ex - print "noes "+ ex.to_s + "\n" cs = nil end return cs end + ## + # returns the bounding box of the changeset. it is possible that some + # or all of the values will be nil, indicating that they are undefined. + def bbox + @bbox ||= [ min_lon, min_lat, max_lon, max_lat ] + end + + def has_valid_bbox? + not bbox.include? nil + end + + ## + # returns area of the changset bbox as a rough comparitive quantity for use of changset displays + def area + if has_valid_bbox? + (max_lon - min_lon) * (max_lat - min_lat) + else + 0 + end + end + + ## + # expand the bounding box to include the given bounding box. also, + # expand a little bit more in the direction of the expansion, so that + # further expansions may be unnecessary. this is an optimisation + # suggested on the wiki page by kleptog. + def update_bbox!(array) + # ensure that bbox is cached and has no nils in it. if there are any + # nils, just use the bounding box update to write over them. + @bbox = bbox.zip(array).collect { |a, b| a.nil? ? b : a } + + # FIXME - this looks nasty and violates DRY... is there any prettier + # way to do this? + @bbox[0] = [-180 * GeoRecord::SCALE, array[0] + EXPAND * (@bbox[0] - @bbox[2])].max if array[0] < @bbox[0] + @bbox[1] = [ -90 * GeoRecord::SCALE, array[1] + EXPAND * (@bbox[1] - @bbox[3])].max if array[1] < @bbox[1] + @bbox[2] = [ 180 * GeoRecord::SCALE, array[2] + EXPAND * (@bbox[2] - @bbox[0])].min if array[2] > @bbox[2] + @bbox[3] = [ 90 * GeoRecord::SCALE, array[3] + EXPAND * (@bbox[3] - @bbox[1])].min if array[3] > @bbox[3] + + # update active record. rails 2.1's dirty handling should take care of + # whether this object needs saving or not. + self.min_lon, self.min_lat, self.max_lon, self.max_lat = @bbox + end + + ## + # the number of elements is also passed in so that we can ensure that + # a single changeset doesn't contain too many elements. this, of course, + # destroys the optimisation described in the bbox method above. + def add_changes!(elements) + self.num_changes += elements + end + + def tags_as_hash + return tags + end + def tags unless @tags @tags = {} @@ -67,15 +154,11 @@ class Changeset < ActiveRecord::Base end def save_with_tags! - t = Time.now - + # do the changeset update and the changeset tags update in the + # same transaction to ensure consistency. Changeset.transaction do - # fixme update modified_at time? - # FIXME there is no modified_at time, should it be added self.save! - end - ChangesetTag.transaction do tags = self.tags ChangesetTag.delete_all(['id = ?', self.id]) @@ -88,6 +171,20 @@ class Changeset < ActiveRecord::Base end end end + + ## + # set the auto-close time to be one hour in the future unless + # that would make it more than 24h long, in which case clip to + # 24h, as this has been decided is a reasonable time limit. + def before_save + if self.is_open? + if (closed_at - created_at) > (MAX_TIME_OPEN - IDLE_TIMEOUT) + self.closed_at = created_at + MAX_TIME_OPEN + else + self.closed_at = Time.now.getutc + IDLE_TIMEOUT + end + end + end def to_xml doc = OSM::API.new.get_xml_doc @@ -110,6 +207,7 @@ class Changeset < ActiveRecord::Base end el1['user'] = user_display_name_cache[self.user_id] unless user_display_name_cache[self.user_id].nil? + el1['uid'] = self.user_id.to_s if self.user.data_public? self.tags.each do |k,v| el2 = XML::Node.new('tag') @@ -119,12 +217,39 @@ class Changeset < ActiveRecord::Base end el1['created_at'] = self.created_at.xmlschema - el1['open'] = self.open.to_s + el1['closed_at'] = self.closed_at.xmlschema unless is_open? + el1['open'] = is_open?.to_s - # FIXME FIXME FIXME: This does not include changes yet! There is - # currently no changeset_id column in the tables as far as I can tell, - # so this is just a scaffold to build on, not a complete to_xml + el1['min_lon'] = (bbox[0].to_f / GeoRecord::SCALE).to_s unless bbox[0].nil? + el1['min_lat'] = (bbox[1].to_f / GeoRecord::SCALE).to_s unless bbox[1].nil? + el1['max_lon'] = (bbox[2].to_f / GeoRecord::SCALE).to_s unless bbox[2].nil? + el1['max_lat'] = (bbox[3].to_f / GeoRecord::SCALE).to_s unless bbox[3].nil? + + # NOTE: changesets don't include the XML of the changes within them, + # they are just structures for tagging. to get the osmChange of a + # changeset, see the download method of the controller. return el1 end + + ## + # update this instance from another instance given and the user who is + # doing the updating. note that this method is not for updating the + # bounding box, only the tags of the changeset. + def update_from(other, user) + # ensure that only the user who opened the changeset may modify it. + unless user.id == self.user_id + raise OSM::APIUserChangesetMismatchError.new + end + + # can't change a closed changeset + unless is_open? + raise OSM::APIChangesetAlreadyClosedError.new(self) + end + + # copy the other's tags + self.tags = other.tags + + save_with_tags! + end end